How do I open a specific message in the default message app?

Question

I subscribe to incoming SMS in my app using the method described here: http://www.devx.com/wireless/Article/39495/0/page/2

With that method I get a message in the form of a android.telephony.SmsMessage. Then I'm planning on opening the default message app using something like this:

Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse("content://mms-sms/conversations/"+threadId));
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intent);

But is there any good way of getting the conversation id for a specific message?